We're getting new carpet and I'd like to keep the cat off of it.
This is my idea:
Put an induction coil under the carpet at the 12 ft opening to family room that is connected to a Hall Effects Sensor. When the collar with a strong magnet in it comes close to the coil the Hall Effects Sensor would detect a voltage change in the current running in the coil. The sensor would create a signal that would trip a relay and sound a buzzer or generate a sound to scare her away. Is that something that is possible? Attached is a cartoon showing my ignorance.

 

Just a buzzer? I think the phrase is annoy and ignore. That is, most animals will soon learn to ignore the buzzer. It might work for a few days. It might also prompt the cat to pee on it.

John

 

I may be wrong but I think RFID might be another way to detect cat proximity. A shaking can of coins makes a noise cats hate.

Also, you simply HAVE to watch this related video. Don't miss it.

 

I may be wrong but I think RFID might be another way to detect cat proximity. A shaking can of coins makes a noise cats hate.

Also, you simply HAVE to watch this related video. Don't miss it.

I looked in to passive RFID but it seems a lot more complicated - way beyond my ability; and expensive.

 

@grantc
Use the invisible fence method - an AM radio signal in a long antenna - under the carpet or under the floor joists in the basement, it works either way. The receiver is on the collar. That way, the receiver picks up a stronger and stronger signal as the cat gets closer - the cat will soon learn when is too close. Too close means he/she will be doing a back flip and letting out a loud yelp. Just buy standard invisible fence supplies (probably chinese knock-offs available on ebay).

 

We're getting new carpet and I'd like to keep the cat off of it.
This is my idea:
Put an induction coil under the carpet at the 12 ft opening to family room that is connected to a Hall Effects Sensor. When the collar with a strong magnet in it comes close to the coil the Hall Effects Sensor would detect a voltage change in the current running in the coil. The sensor would create a signal that would trip a relay and sound a buzzer or generate a sound to scare her away. Is that something that is possible? Attached is a cartoon showing my ignorance.

Heisenbergs uncertainty principle shows that it is impossible to predict which direction a scared cat will run. Or maybe it was Shrodinger. Anyway there are quantum tunneling effects which need to be considered as well, the equilibrium cat position may well be sleeping on the chair within the unintended room.